gcc/df.h

   1 /* Form lists of pseudo register references for autoinc optimization
   2    for GNU compiler.  This is part of flow optimization.
   3    Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008,
   4    2009, 2010  Free Software Foundation, Inc.
   5    Originally contributed by Michael P. Hayes
   6              (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
   7    Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
   8              and Kenneth Zadeck (zadeck@naturalbridge.com).
   9
  10 This file is part of GCC.
  11
  12 GCC is free software; you can redistribute it and/or modify it under
  13 the terms of the GNU General Public License as published by the Free
  14 Software Foundation; either version 3, or (at your option) any later
  15 version.
  16
  17 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  18 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20 for more details.
  21
  22 You should have received a copy of the GNU General Public License
  23 along with GCC; see the file COPYING3.  If not see
  24 <http://www.gnu.org/licenses/>.  */
  25
  26 #ifndef GCC_DF_H
  27 #define GCC_DF_H
  28
  29 #include "bitmap.h"
  30 #include "regset.h"
  31 #include "sbitmap.h"
  32 #include "basic-block.h"
  33 #include "alloc-pool.h"
  34 #include "timevar.h"
  35
  36 struct dataflow;
  37 struct df;
  38 struct df_problem;
  39 struct df_link;
  40 struct df_insn_info;
  41 union df_ref_d;
  42
  43 /* Data flow problems.  All problems must have a unique id here.  */
  44
  45 /* Scanning is not really a dataflow problem, but it is useful to have
  46    the basic block functions in the vector so that things get done in
  47    a uniform manner.  The last four problems can be added or deleted
  48    at any time are always defined (though LIVE is always there at -O2
  49    or higher); the others are always there.  */
  50 #define DF_SCAN    0
  51 #define DF_LR      1      /* Live Registers backward. */
  52 #define DF_LIVE    2      /* Live Registers & Uninitialized Registers */
  53 #define DF_RD      3      /* Reaching Defs. */
  54 #define DF_CHAIN   4      /* Def-Use and/or Use-Def Chains. */
  55 #define DF_BYTE_LR 5      /* Subreg tracking lr.  */
  56 #define DF_NOTE    6      /* REG_DEF and REG_UNUSED notes. */
  57 #define DF_MD      7      /* Multiple Definitions. */
  58
  59 #define DF_LAST_PROBLEM_PLUS1 (DF_MD + 1)
  60
  61 /* Dataflow direction.  */
  62 enum df_flow_dir
  63   {
  64     DF_NONE,
  65     DF_FORWARD,
  66     DF_BACKWARD
  67   };
  68
  69 /* Used in the byte scanning to determine if may or must info is to be
  70    returned.  */
  71 enum df_mm
  72   {
  73     DF_MM_MAY,
  74     DF_MM_MUST
  75   };
  76
  77 /* Descriminator for the various df_ref types.  */
  78 enum df_ref_class {DF_REF_BASE, DF_REF_ARTIFICIAL, DF_REF_REGULAR, DF_REF_EXTRACT};
  79
  80 /* The first of these us a set of a registers.  The remaining three
  81    are all uses of a register (the mem_load and mem_store relate to
  82    how the register as an addressing operand).  */
  83 enum df_ref_type {DF_REF_REG_DEF, DF_REF_REG_USE,
  84                   DF_REF_REG_MEM_LOAD, DF_REF_REG_MEM_STORE};
  85
  86 enum df_ref_flags
  87   {
  88     /* This flag is set if this ref occurs inside of a conditional
  89        execution instruction.  */
  90     DF_REF_CONDITIONAL = 1 << 0,
  91
  92     /* If this flag is set for an artificial use or def, that ref
  93        logically happens at the top of the block.  If it is not set
  94        for an artificial use or def, that ref logically happens at the
  95        bottom of the block.  This is never set for regular refs.  */
  96     DF_REF_AT_TOP = 1 << 1,
  97
  98     /* This flag is set if the use is inside a REG_EQUAL or REG_EQUIV
  99        note.  */
 100     DF_REF_IN_NOTE = 1 << 2,
 101
 102     /* This bit is true if this ref can make regs_ever_live true for
 103        this regno.  */
 104     DF_HARD_REG_LIVE = 1 << 3,
 105
 106
 107     /* This flag is set if this ref is a partial use or def of the
 108        associated register.  */
 109     DF_REF_PARTIAL = 1 << 4,
 110
 111     /* Read-modify-write refs generate both a use and a def and
 112        these are marked with this flag to show that they are not
 113        independent.  */
 114     DF_REF_READ_WRITE = 1 << 5,
 115
 116     /* This flag is set if this ref, generally a def, may clobber the
 117        referenced register.  This is generally only set for hard
 118        registers that cross a call site.  With better information
 119        about calls, some of these could be changed in the future to
 120        DF_REF_MUST_CLOBBER.  */
 121     DF_REF_MAY_CLOBBER = 1 << 6,
 122
 123     /* This flag is set if this ref, generally a def, is a real
 124        clobber. This is not currently set for registers live across a
 125        call because that clobbering may or may not happen.
 126
 127        Most of the uses of this are with sets that have a
 128        GET_CODE(..)==CLOBBER.  Note that this is set even if the
 129        clobber is to a subreg.  So in order to tell if the clobber
 130        wipes out the entire register, it is necessary to also check
 131        the DF_REF_PARTIAL flag.  */
 132     DF_REF_MUST_CLOBBER = 1 << 7,
 133
 134
 135     /* If the ref has one of the following two flags set, then the
 136        struct df_ref can be cast to struct df_ref_extract to access
 137        the width and offset fields.  */
 138
 139     /* This flag is set if the ref contains a SIGN_EXTRACT.  */
 140     DF_REF_SIGN_EXTRACT = 1 << 8,
 141
 142     /* This flag is set if the ref contains a ZERO_EXTRACT.  */
 143     DF_REF_ZERO_EXTRACT = 1 << 9,
 144
 145     /* This flag is set if the ref contains a STRICT_LOW_PART.  */
 146     DF_REF_STRICT_LOW_PART = 1 << 10,
 147
 148     /* This flag is set if the ref contains a SUBREG.  */
 149     DF_REF_SUBREG = 1 << 11,
 150
 151
 152     /* This bit is true if this ref is part of a multiword hardreg.  */
 153     DF_REF_MW_HARDREG = 1 << 12,
 154
 155     /* This flag is set if this ref is a usage of the stack pointer by
 156        a function call.  */
 157     DF_REF_CALL_STACK_USAGE = 1 << 13,
 158
 159     /* This flag is used for verification of existing refs. */
 160     DF_REF_REG_MARKER = 1 << 14,
 161
 162     /* This flag is set if this ref is inside a pre/post modify.  */
 163     DF_REF_PRE_POST_MODIFY = 1 << 15
 164
 165   };
 166
 167 /* The possible ordering of refs within the df_ref_info.  */
 168 enum df_ref_order
 169   {
 170     /* There is not table.  */
 171     DF_REF_ORDER_NO_TABLE,
 172
 173     /* There is a table of refs but it is not (or no longer) organized
 174        by one of the following methods.  */
 175     DF_REF_ORDER_UNORDERED,
 176     DF_REF_ORDER_UNORDERED_WITH_NOTES,
 177
 178     /* Organize the table by reg order, all of the refs with regno 0
 179        followed by all of the refs with regno 1 ... .  Within all of
 180        the regs for a particular regno, the refs are unordered.  */
 181     DF_REF_ORDER_BY_REG,
 182
 183     /* For uses, the refs within eq notes may be added for
 184        DF_REF_ORDER_BY_REG.  */
 185     DF_REF_ORDER_BY_REG_WITH_NOTES,
 186
 187     /* Organize the refs in insn order.  The insns are ordered within a
 188        block, and the blocks are ordered by FOR_ALL_BB.  */
 189     DF_REF_ORDER_BY_INSN,
 190
 191     /* For uses, the refs within eq notes may be added for
 192        DF_REF_ORDER_BY_INSN.  */
 193     DF_REF_ORDER_BY_INSN_WITH_NOTES
 194   };
 195
 196 /* Function prototypes added to df_problem instance.  */
 197
 198 /* Allocate the problem specific data.  */
 199 typedef void (*df_alloc_function) (bitmap);
 200
 201 /* This function is called if the problem has global data that needs
 202    to be cleared when ever the set of blocks changes.  The bitmap
 203    contains the set of blocks that may require special attention.
 204    This call is only made if some of the blocks are going to change.
 205    If everything is to be deleted, the wholesale deletion mechanisms
 206    apply. */
 207 typedef void (*df_reset_function) (bitmap);
 208
 209 /* Free the basic block info.  Called from the block reordering code
 210    to get rid of the blocks that have been squished down.   */
 211 typedef void (*df_free_bb_function) (basic_block, void *);
 212
 213 /* Local compute function.  */
 214 typedef void (*df_local_compute_function) (bitmap);
 215
 216 /* Init the solution specific data.  */
 217 typedef void (*df_init_function) (bitmap);
 218
 219 /* Iterative dataflow function.  */
 220 typedef void (*df_dataflow_function) (struct dataflow *, bitmap, int *, int);
 221
 222 /* Confluence operator for blocks with 0 out (or in) edges.  */
 223 typedef void (*df_confluence_function_0) (basic_block);
 224
 225 /* Confluence operator for blocks with 1 or more out (or in) edges.  */
 226 typedef void (*df_confluence_function_n) (edge);
 227
 228 /* Transfer function for blocks.  */
 229 typedef bool (*df_transfer_function) (int);
 230
 231 /* Function to massage the information after the problem solving.  */
 232 typedef void (*df_finalizer_function) (bitmap);
 233
 234 /* Function to free all of the problem specific datastructures.  */
 235 typedef void (*df_free_function) (void);
 236
 237 /* Function to remove this problem from the stack of dataflow problems
 238    without effecting the other problems in the stack except for those
 239    that depend on this problem.  */
 240 typedef void (*df_remove_problem_function) (void);
 241
 242 /* Function to dump basic block independent results to FILE.  */
 243 typedef void (*df_dump_problem_function) (FILE *);
 244
 245 /* Function to dump top or bottom of basic block results to FILE.  */
 246 typedef void (*df_dump_bb_problem_function) (basic_block, FILE *);
 247
 248 /* Function to dump top or bottom of basic block results to FILE.  */
 249 typedef void (*df_verify_solution_start) (void);
 250
 251 /* Function to dump top or bottom of basic block results to FILE.  */
 252 typedef void (*df_verify_solution_end) (void);
 253
 254 /* The static description of a dataflow problem to solve.  See above
 255    typedefs for doc for the function fields.  */
 256
 257 struct df_problem {
 258   /* The unique id of the problem.  This is used it index into
 259      df->defined_problems to make accessing the problem data easy.  */
 260   unsigned int id;
 261   enum df_flow_dir dir;                 /* Dataflow direction.  */
 262   df_alloc_function alloc_fun;
 263   df_reset_function reset_fun;
 264   df_free_bb_function free_bb_fun;
 265   df_local_compute_function local_compute_fun;
 266   df_init_function init_fun;
 267   df_dataflow_function dataflow_fun;
 268   df_confluence_function_0 con_fun_0;
 269   df_confluence_function_n con_fun_n;
 270   df_transfer_function trans_fun;
 271   df_finalizer_function finalize_fun;
 272   df_free_function free_fun;
 273   df_remove_problem_function remove_problem_fun;
 274   df_dump_problem_function dump_start_fun;
 275   df_dump_bb_problem_function dump_top_fun;
 276   df_dump_bb_problem_function dump_bottom_fun;
 277   df_verify_solution_start verify_start_fun;
 278   df_verify_solution_end verify_end_fun;
 279   struct df_problem *dependent_problem;
 280
 281   /* The timevar id associated with this pass.  */
 282   timevar_id_t tv_id;
 283
 284   /* True if the df_set_blocks should null out the basic block info if
 285      this block drops out of df->blocks_to_analyze.  */
 286   bool free_blocks_on_set_blocks;
 287 };
 288
 289
 290 /* The specific instance of the problem to solve.  */
 291 struct dataflow
 292 {
 293   struct df_problem *problem;           /* The problem to be solved.  */
 294
 295   /* Array indexed by bb->index, that contains basic block problem and
 296      solution specific information.  */
 297   void **block_info;
 298   unsigned int block_info_size;
 299
 300   /* The pool to allocate the block_info from. */
 301   alloc_pool block_pool;
 302
 303   /* The lr and live problems have their transfer functions recomputed
 304      only if necessary.  This is possible for them because, the
 305      problems are kept active for the entire backend and their
 306      transfer functions are indexed by the REGNO.  These are not
 307      defined for any other problem.  */
 308   bitmap out_of_date_transfer_functions;
 309
 310   /* Other problem specific data that is not on a per basic block
 311      basis.  The structure is generally defined privately for the
 312      problem.  The exception being the scanning problem where it is
 313      fully public.  */
 314   void *problem_data;
 315
 316   /* Local flags for some of the problems. */
 317   unsigned int local_flags;
 318
 319   /* True if this problem of this instance has been initialized.  This
 320      is used by the dumpers to keep garbage out of the dumps if, for
 321      debugging a dump is produced before the first call to
 322      df_analyze after a new problem is added.  */
 323   bool computed;
 324
 325   /* True if the something has changed which invalidates the dataflow
 326      solutions.  Note that this bit is always true for all problems except
 327      lr and live.  */
 328   bool solutions_dirty;
 329
 330   /* If true, this pass is deleted by df_finish_pass.  This is never
 331      true for DF_SCAN and DF_LR.  It is true for DF_LIVE if optimize >
 332      1.  It is always true for the other problems.  */
 333   bool optional_p;
 334 };
 335
 336
 337 /* The set of multiword hardregs used as operands to this
 338    instruction. These are factored into individual uses and defs but
 339    the aggregate is still needed to service the REG_DEAD and
 340    REG_UNUSED notes.  */
 341 struct df_mw_hardreg
 342 {
 343   rtx mw_reg;                   /* The multiword hardreg.  */
 344   /* These two bitfields are intentionally oversized, in the hope that
 345      accesses to 16-bit fields will usually be quicker.  */
 346   ENUM_BITFIELD(df_ref_type) type : 16;
 347                                 /* Used to see if the ref is read or write.  */
 348   int flags : 16;               /* Various df_ref_flags.  */
 349   unsigned int start_regno;     /* First word of the multi word subreg.  */
 350   unsigned int end_regno;       /* Last word of the multi word subreg.  */
 351   unsigned int mw_order;        /* Same as df_ref.ref_order.  */
 352 };
 353
 354
 355 /* Define a register reference structure.  One of these is allocated
 356     for every register reference (use or def).  Note some register
 357     references (e.g., post_inc, subreg) generate both a def and a use.  */
 358 struct df_base_ref
 359 {
 360   /* These three bitfields are intentionally oversized, in the hope that
 361      accesses to 8 and 16-bit fields will usually be quicker.  */
 362   ENUM_BITFIELD(df_ref_class) cl : 8;
 363
 364   ENUM_BITFIELD(df_ref_type) type : 8;
 365                                 /* Type of ref.  */
 366   int flags : 16;               /* Various df_ref_flags.  */
 367   rtx reg;                      /* The register referenced.  */
 368   struct df_link *chain;        /* Head of def-use, use-def.  */
 369   /* Pointer to the insn info of the containing instruction.  FIXME!
 370      Currently this is NULL for artificial refs but this will be used
 371      when FUDs are added.  */
 372   struct df_insn_info *insn_info;
 373   /* For each regno, there are three chains of refs, one for the uses,
 374      the eq_uses and the defs.  These chains go thru the refs
 375      themselves rather than using an external structure.  */
 376   union df_ref_d *next_reg;     /* Next ref with same regno and type.  */
 377   union df_ref_d *prev_reg;     /* Prev ref with same regno and type.  */
 378   unsigned int regno;           /* The register number referenced.  */
 379   /* Location in the ref table.  This is only valid after a call to
 380      df_maybe_reorganize_[use,def]_refs which is an expensive operation.  */
 381   int id;
 382   /* The index at which the operand was scanned in the insn.  This is
 383      used to totally order the refs in an insn.  */
 384   unsigned int ref_order;
 385 };
 386
 387
 388 /* The three types of df_refs.  Note that the df_ref_extract is an
 389    extension of the df_regular_ref, not the df_base_ref.  */
 390 struct df_artificial_ref
 391 {
 392   struct df_base_ref base;
 393
 394   /* Artificial refs do not have an insn, so to get the basic block,
 395      it must be explicitly here.  */
 396   basic_block bb;
 397 };
 398
 399
 400 struct df_regular_ref
 401 {
 402   struct df_base_ref base;
 403   /* The loc is the address in the insn of the reg.  This is not
 404      defined for special registers, such as clobbers and stack
 405      pointers that are also associated with call insns and so those
 406      just use the base.  */
 407   rtx *loc;
 408 };
 409
 410
 411 /* A df_ref_extract is just a df_ref with a width and offset field at
 412    the end of it.  It is used to hold this information if the ref was
 413    wrapped by a SIGN_EXTRACT or a ZERO_EXTRACT and to pass this info
 414    to passes that wish to process partial regs precisely.  */
 415 struct df_extract_ref
 416 {
 417   struct df_regular_ref base;
 418   int width;
 419   int offset;
 420   enum machine_mode mode;
 421 };
 422
 423 /* Union of the different kinds of defs/uses placeholders.  */
 424 union df_ref_d
 425 {
 426   struct df_base_ref base;
 427   struct df_regular_ref regular_ref;
 428   struct df_artificial_ref artificial_ref;
 429   struct df_extract_ref extract_ref;
 430 };
 431 typedef union df_ref_d *df_ref;
 432
 433
 434 /* One of these structures is allocated for every insn.  */
 435 struct df_insn_info
 436 {
 437   rtx insn;                     /* The insn this info comes from.  */
 438   df_ref *defs;                 /* Head of insn-def chain.  */
 439   df_ref *uses;                 /* Head of insn-use chain.  */
 440   /* Head of insn-use chain for uses in REG_EQUAL/EQUIV notes.  */
 441   df_ref *eq_uses;
 442   struct df_mw_hardreg **mw_hardregs;
 443   /* The logical uid of the insn in the basic block.  This is valid
 444      after any call to df_analyze but may rot after insns are added,
 445      deleted or moved. */
 446   int luid;
 447 };
 448
 449 /* These links are used for ref-ref chains.  Currently only DEF-USE and
 450    USE-DEF chains can be built by DF.  */
 451 struct df_link
 452 {
 453   df_ref ref;
 454   struct df_link *next;
 455 };
 456
 457 \f
 458 enum df_chain_flags
 459 {
 460   /* Flags that control the building of chains.  */
 461   DF_DU_CHAIN      =  1, /* Build DU chains.  */
 462   DF_UD_CHAIN      =  2  /* Build UD chains.  */
 463 };
 464
 465 enum df_changeable_flags
 466 {
 467   /* Scanning flags.  */
 468   /* Flag to control the running of dce as a side effect of building LR.  */
 469   DF_LR_RUN_DCE           = 1 << 0, /* Run DCE.  */
 470   DF_NO_HARD_REGS         = 1 << 1, /* Skip hard registers in RD and CHAIN Building.  */
 471
 472   DF_EQ_NOTES             = 1 << 2, /* Build chains with uses present in EQUIV/EQUAL notes. */
 473   DF_NO_REGS_EVER_LIVE    = 1 << 3, /* Do not compute the regs_ever_live.  */
 474
 475   /* Cause df_insn_rescan df_notes_rescan and df_insn_delete, to
 476   return immediately.  This is used by passes that know how to update
 477   the scanning them selves.  */
 478   DF_NO_INSN_RESCAN       = 1 << 4,
 479
 480   /* Cause df_insn_rescan df_notes_rescan and df_insn_delete, to
 481   return after marking the insn for later processing.  This allows all
 482   rescans to be batched.  */
 483   DF_DEFER_INSN_RESCAN    = 1 << 5,
 484
 485   DF_VERIFY_SCHEDULED     = 1 << 6
 486 };
 487
 488 /* Two of these structures are inline in df, one for the uses and one
 489    for the defs.  This structure is only contains the refs within the
 490    boundary of the df_set_blocks if that has been defined.  */
 491 struct df_ref_info
 492 {
 493   df_ref *refs;                 /* Ref table, indexed by id.  */
 494   unsigned int *begin;          /* First ref_index for this pseudo.  */
 495   unsigned int *count;          /* Count of refs for this pseudo.  */
 496   unsigned int refs_size;       /* Size of currently allocated refs table.  */
 497
 498   /* Table_size is the number of elements in the refs table.  This
 499      will also be the width of the bitvectors in the rd and ru
 500      problems.  Total_size is the number of refs.  These will be the
 501      same if the focus has not been reduced by df_set_blocks.  If the
 502      focus has been reduced, table_size will be smaller since it only
 503      contains the refs in the set blocks.  */
 504   unsigned int table_size;
 505   unsigned int total_size;
 506
 507   enum df_ref_order ref_order;
 508 };
 509
 510 /* Three of these structures are allocated for every pseudo reg. One
 511    for the uses, one for the eq_uses and one for the defs.  */
 512 struct df_reg_info
 513 {
 514   /* Head of chain for refs of that type and regno.  */
 515   df_ref reg_chain;
 516   /* Number of refs in the chain.  */
 517   unsigned int n_refs;
 518 };
 519
 520
 521 /*----------------------------------------------------------------------------
 522    Problem data for the scanning dataflow problem.  Unlike the other
 523    dataflow problems, the problem data for scanning is fully exposed and
 524    used by owners of the problem.
 525 ----------------------------------------------------------------------------*/
 526
 527 struct df
 528 {
 529
 530   /* The set of problems to be solved is stored in two arrays.  In
 531      PROBLEMS_IN_ORDER, the problems are stored in the order that they
 532      are solved.  This is an internally dense array that may have
 533      nulls at the end of it.  In PROBLEMS_BY_INDEX, the problem is
 534      stored by the value in df_problem.id.  These are used to access
 535      the problem local data without having to search the first
 536      array.  */
 537
 538   struct dataflow *problems_in_order[DF_LAST_PROBLEM_PLUS1];
 539   struct dataflow *problems_by_index[DF_LAST_PROBLEM_PLUS1];
 540
 541   /* If not NULL, this subset of blocks of the program to be
 542      considered for analysis.  At certain times, this will contain all
 543      the blocks in the function so it cannot be used as an indicator
 544      of if we are analyzing a subset.  See analyze_subset.  */
 545   bitmap blocks_to_analyze;
 546
 547   /* The following information is really the problem data for the
 548      scanning instance but it is used too often by the other problems
 549      to keep getting it from there.  */
 550   struct df_ref_info def_info;   /* Def info.  */
 551   struct df_ref_info use_info;   /* Use info.  */
 552
 553   /* The following three arrays are allocated in parallel.   They contain
 554      the sets of refs of each type for each reg.  */
 555   struct df_reg_info **def_regs;       /* Def reg info.  */
 556   struct df_reg_info **use_regs;       /* Eq_use reg info.  */
 557   struct df_reg_info **eq_use_regs;    /* Eq_use info.  */
 558   unsigned int regs_size;       /* Size of currently allocated regs table.  */
 559   unsigned int regs_inited;     /* Number of regs with reg_infos allocated.  */
 560
 561
 562   struct df_insn_info **insns;   /* Insn table, indexed by insn UID.  */
 563   unsigned int insns_size;       /* Size of insn table.  */
 564
 565   int num_problems_defined;
 566
 567   bitmap hardware_regs_used;     /* The set of hardware registers used.  */
 568   /* The set of hard regs that are in the artificial uses at the end
 569      of a regular basic block.  */
 570   bitmap regular_block_artificial_uses;
 571   /* The set of hard regs that are in the artificial uses at the end
 572      of a basic block that has an EH pred.  */
 573   bitmap eh_block_artificial_uses;
 574   /* The set of hardware registers live on entry to the function.  */
 575   bitmap entry_block_defs;
 576   bitmap exit_block_uses;        /* The set of hardware registers used in exit block.  */
 577
 578   /* Insns to delete, rescan or reprocess the notes at next
 579      df_rescan_all or df_process_deferred_rescans. */
 580   bitmap insns_to_delete;
 581   bitmap insns_to_rescan;
 582   bitmap insns_to_notes_rescan;
 583   int *postorder;                /* The current set of basic blocks
 584                                     in reverse postorder.  */
 585   int *postorder_inverted;       /* The current set of basic blocks
 586                                     in reverse postorder of inverted CFG.  */
 587   int n_blocks;                  /* The number of blocks in reverse postorder.  */
 588   int n_blocks_inverted;         /* The number of blocks
 589                                     in reverse postorder of inverted CFG.  */
 590
 591   /* An array [FIRST_PSEUDO_REGISTER], indexed by regno, of the number
 592      of refs that qualify as being real hard regs uses.  Artificial
 593      uses and defs as well as refs in eq notes are ignored.  If the
 594      ref is a def, it cannot be a MAY_CLOBBER def.  If the ref is a
 595      use, it cannot be the emim_reg_set or be the frame or arg pointer
 596      register.
 597
 598      IT IS NOT ACCEPTABLE TO MANUALLY CHANGE THIS ARRAY.  This array
 599      always reflects the actual number of refs in the insn stream that
 600      satisfy the above criteria.  */
 601   unsigned int *hard_regs_live_count;
 602
 603   /* This counter provides a way to totally order refs without using
 604      addresses.  It is incremented whenever a ref is created.  */
 605   unsigned int ref_order;
 606
 607   /* Problem specific control information.  This is a combination of
 608      enum df_changeable_flags values.  */
 609   int changeable_flags : 8;
 610
 611   /* If this is true, then only a subset of the blocks of the program
 612      is considered to compute the solutions of dataflow problems.  */
 613   bool analyze_subset;
 614
 615   /* True if someone added or deleted something from regs_ever_live so
 616      that the entry and exit blocks need be reprocessed.  */
 617   bool redo_entry_and_exit;
 618 };
 619
 620 #define DF_SCAN_BB_INFO(BB) (df_scan_get_bb_info((BB)->index))
 621 #define DF_RD_BB_INFO(BB) (df_rd_get_bb_info((BB)->index))
 622 #define DF_LR_BB_INFO(BB) (df_lr_get_bb_info((BB)->index))
 623 #define DF_LIVE_BB_INFO(BB) (df_live_get_bb_info((BB)->index))
 624 #define DF_BYTE_LR_BB_INFO(BB) (df_byte_lr_get_bb_info((BB)->index))
 625 #define DF_MD_BB_INFO(BB) (df_md_get_bb_info((BB)->index))
 626
 627 /* Most transformations that wish to use live register analysis will
 628    use these macros.  This info is the and of the lr and live sets.  */
 629 #define DF_LIVE_IN(BB) (DF_LIVE_BB_INFO(BB)->in)
 630 #define DF_LIVE_OUT(BB) (DF_LIVE_BB_INFO(BB)->out)
 631
 632 /* These macros are used by passes that are not tolerant of
 633    uninitialized variables.  This intolerance should eventually
 634    be fixed.  */
 635 #define DF_LR_IN(BB) (DF_LR_BB_INFO(BB)->in)
 636 #define DF_LR_OUT(BB) (DF_LR_BB_INFO(BB)->out)
 637
 638 /* These macros are used by passes that are not tolerant of
 639    uninitialized variables.  This intolerance should eventually
 640    be fixed.  */
 641 #define DF_BYTE_LR_IN(BB) (DF_BYTE_LR_BB_INFO(BB)->in)
 642 #define DF_BYTE_LR_OUT(BB) (DF_BYTE_LR_BB_INFO(BB)->out)
 643
 644 /* Macros to access the elements within the ref structure.  */
 645
 646
 647 #define DF_REF_REAL_REG(REF) (GET_CODE ((REF)->base.reg) == SUBREG \
 648                                 ? SUBREG_REG ((REF)->base.reg) : ((REF)->base.reg))
 649 #define DF_REF_REGNO(REF) ((REF)->base.regno)
 650 #define DF_REF_REAL_LOC(REF) (GET_CODE (*((REF)->regular_ref.loc)) == SUBREG \
 651                                ? &SUBREG_REG (*((REF)->regular_ref.loc)) : ((REF)->regular_ref.loc))
 652 #define DF_REF_REG(REF) ((REF)->base.reg)
 653 #define DF_REF_LOC(REF) ((DF_REF_CLASS(REF) == DF_REF_REGULAR || DF_REF_CLASS(REF) == DF_REF_EXTRACT) ? \
 654                          (REF)->regular_ref.loc : NULL)
 655 #define DF_REF_BB(REF) (DF_REF_IS_ARTIFICIAL(REF) ? \
 656                         (REF)->artificial_ref.bb : BLOCK_FOR_INSN (DF_REF_INSN(REF)))
 657 #define DF_REF_BBNO(REF) (DF_REF_BB (REF)->index)
 658 #define DF_REF_INSN_INFO(REF) ((REF)->base.insn_info)
 659 #define DF_REF_INSN(REF) ((REF)->base.insn_info->insn)
 660 #define DF_REF_INSN_UID(REF) (INSN_UID (DF_REF_INSN(REF)))
 661 #define DF_REF_CLASS(REF) ((REF)->base.cl)
 662 #define DF_REF_TYPE(REF) ((REF)->base.type)
 663 #define DF_REF_CHAIN(REF) ((REF)->base.chain)
 664 #define DF_REF_ID(REF) ((REF)->base.id)
 665 #define DF_REF_FLAGS(REF) ((REF)->base.flags)
 666 #define DF_REF_FLAGS_IS_SET(REF, v) ((DF_REF_FLAGS (REF) & (v)) != 0)
 667 #define DF_REF_FLAGS_SET(REF, v) (DF_REF_FLAGS (REF) |= (v))
 668 #define DF_REF_FLAGS_CLEAR(REF, v) (DF_REF_FLAGS (REF) &= ~(v))
 669 #define DF_REF_ORDER(REF) ((REF)->base.ref_order)
 670 /* If DF_REF_IS_ARTIFICIAL () is true, this is not a real
 671    definition/use, but an artificial one created to model always live
 672    registers, eh uses, etc.  */
 673 #define DF_REF_IS_ARTIFICIAL(REF) (DF_REF_CLASS(REF) == DF_REF_ARTIFICIAL)
 674 #define DF_REF_REG_MARK(REF) (DF_REF_FLAGS_SET ((REF),DF_REF_REG_MARKER))
 675 #define DF_REF_REG_UNMARK(REF) (DF_REF_FLAGS_CLEAR ((REF),DF_REF_REG_MARKER))
 676 #define DF_REF_IS_REG_MARKED(REF) (DF_REF_FLAGS_IS_SET ((REF),DF_REF_REG_MARKER))
 677 #define DF_REF_NEXT_REG(REF) ((REF)->base.next_reg)
 678 #define DF_REF_PREV_REG(REF) ((REF)->base.prev_reg)
 679 /* The following two macros may only be applied if one of
 680    DF_REF_SIGN_EXTRACT | DF_REF_ZERO_EXTRACT is true. */
 681 #define DF_REF_EXTRACT_WIDTH(REF) ((REF)->extract_ref.width)
 682 #define DF_REF_EXTRACT_OFFSET(REF) ((REF)->extract_ref.offset)
 683 #define DF_REF_EXTRACT_MODE(REF) ((REF)->extract_ref.mode)
 684
 685 /* Macros to determine the reference type.  */
 686 #define DF_REF_REG_DEF_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_DEF)
 687 #define DF_REF_REG_USE_P(REF) ((REF) && !DF_REF_REG_DEF_P (REF))
 688 #define DF_REF_REG_MEM_STORE_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_STORE)
 689 #define DF_REF_REG_MEM_LOAD_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_LOAD)
 690 #define DF_REF_REG_MEM_P(REF) (DF_REF_REG_MEM_STORE_P (REF) \
 691                                || DF_REF_REG_MEM_LOAD_P (REF))
 692
 693 #define DF_MWS_REG_DEF_P(MREF) (DF_MWS_TYPE (MREF) == DF_REF_REG_DEF)
 694 #define DF_MWS_REG_USE_P(MREF) ((MREF) && !DF_MWS_REG_DEF_P (MREF))
 695 #define DF_MWS_TYPE(MREF) ((MREF)->type)
 696
 697 /* Macros to get the refs out of def_info or use_info refs table.  If
 698    the focus of the dataflow has been set to some subset of blocks
 699    with df_set_blocks, these macros will only find the uses and defs
 700    in that subset of blocks.
 701
 702    These macros should be used with care.  The def macros are only
 703    usable after a call to df_maybe_reorganize_def_refs and the use
 704    macros are only usable after a call to
 705    df_maybe_reorganize_use_refs.  HOWEVER, BUILDING AND USING THESE
 706    ARRAYS ARE A CACHE LOCALITY KILLER.  */
 707
 708 #define DF_DEFS_TABLE_SIZE() (df->def_info.table_size)
 709 #define DF_DEFS_GET(ID) (df->def_info.refs[(ID)])
 710 #define DF_DEFS_SET(ID,VAL) (df->def_info.refs[(ID)]=(VAL))
 711 #define DF_DEFS_COUNT(ID) (df->def_info.count[(ID)])
 712 #define DF_DEFS_BEGIN(ID) (df->def_info.begin[(ID)])
 713 #define DF_USES_TABLE_SIZE() (df->use_info.table_size)
 714 #define DF_USES_GET(ID) (df->use_info.refs[(ID)])
 715 #define DF_USES_SET(ID,VAL) (df->use_info.refs[(ID)]=(VAL))
 716 #define DF_USES_COUNT(ID) (df->use_info.count[(ID)])
 717 #define DF_USES_BEGIN(ID) (df->use_info.begin[(ID)])
 718
 719 /* Macros to access the register information from scan dataflow record.  */
 720
 721 #define DF_REG_SIZE(DF) (df->regs_inited)
 722 #define DF_REG_DEF_GET(REG) (df->def_regs[(REG)])
 723 #define DF_REG_DEF_CHAIN(REG) (df->def_regs[(REG)]->reg_chain)
 724 #define DF_REG_DEF_COUNT(REG) (df->def_regs[(REG)]->n_refs)
 725 #define DF_REG_USE_GET(REG) (df->use_regs[(REG)])
 726 #define DF_REG_USE_CHAIN(REG) (df->use_regs[(REG)]->reg_chain)
 727 #define DF_REG_USE_COUNT(REG) (df->use_regs[(REG)]->n_refs)
 728 #define DF_REG_EQ_USE_GET(REG) (df->eq_use_regs[(REG)])
 729 #define DF_REG_EQ_USE_CHAIN(REG) (df->eq_use_regs[(REG)]->reg_chain)
 730 #define DF_REG_EQ_USE_COUNT(REG) (df->eq_use_regs[(REG)]->n_refs)
 731
 732 /* Macros to access the elements within the reg_info structure table.  */
 733
 734 #define DF_REGNO_FIRST_DEF(REGNUM) \
 735 (DF_REG_DEF_GET(REGNUM) ? DF_REG_DEF_GET(REGNUM) : 0)
 736 #define DF_REGNO_LAST_USE(REGNUM) \
 737 (DF_REG_USE_GET(REGNUM) ? DF_REG_USE_GET(REGNUM) : 0)
 738
 739 /* Macros to access the elements within the insn_info structure table.  */
 740
 741 #define DF_INSN_SIZE() ((df)->insns_size)
 742 #define DF_INSN_INFO_GET(INSN) (df->insns[(INSN_UID(INSN))])
 743 #define DF_INSN_INFO_SET(INSN,VAL) (df->insns[(INSN_UID (INSN))]=(VAL))
 744 #define DF_INSN_INFO_LUID(II) ((II)->luid)
 745 #define DF_INSN_INFO_DEFS(II) ((II)->defs)
 746 #define DF_INSN_INFO_USES(II) ((II)->uses)
 747 #define DF_INSN_INFO_EQ_USES(II) ((II)->eq_uses)
 748
 749 #define DF_INSN_LUID(INSN) (DF_INSN_INFO_LUID (DF_INSN_INFO_GET(INSN)))
 750 #define DF_INSN_DEFS(INSN) (DF_INSN_INFO_DEFS (DF_INSN_INFO_GET(INSN)))
 751 #define DF_INSN_USES(INSN) (DF_INSN_INFO_USES (DF_INSN_INFO_GET(INSN)))
 752 #define DF_INSN_EQ_USES(INSN) (DF_INSN_INFO_EQ_USES (DF_INSN_INFO_GET(INSN)))
 753
 754 #define DF_INSN_UID_GET(UID) (df->insns[(UID)])
 755 #define DF_INSN_UID_SET(UID,VAL) (df->insns[(UID)]=(VAL))
 756 #define DF_INSN_UID_SAFE_GET(UID) (((unsigned)(UID) < DF_INSN_SIZE())   \
 757                                      ? DF_INSN_UID_GET (UID) \
 758                                      : NULL)
 759 #define DF_INSN_UID_LUID(INSN) (DF_INSN_UID_GET(INSN)->luid)
 760 #define DF_INSN_UID_DEFS(INSN) (DF_INSN_UID_GET(INSN)->defs)
 761 #define DF_INSN_UID_USES(INSN) (DF_INSN_UID_GET(INSN)->uses)
 762 #define DF_INSN_UID_EQ_USES(INSN) (DF_INSN_UID_GET(INSN)->eq_uses)
 763 #define DF_INSN_UID_MWS(INSN) (DF_INSN_UID_GET(INSN)->mw_hardregs)
 764
 765 /* An obstack for bitmap not related to specific dataflow problems.
 766    This obstack should e.g. be used for bitmaps with a short life time
 767    such as temporary bitmaps.  This obstack is declared in df-core.c.  */
 768
 769 extern bitmap_obstack df_bitmap_obstack;
 770
 771
 772 /* One of these structures is allocated for every basic block.  */
 773 struct df_scan_bb_info
 774 {
 775   /* The entry block has many artificial defs and these are at the
 776      bottom of the block.
 777
 778      Blocks that are targets of exception edges may have some
 779      artificial defs.  These are logically located at the top of the
 780      block.
 781
 782      Blocks that are the targets of non-local goto's have the hard
 783      frame pointer defined at the top of the block.  */
 784   df_ref *artificial_defs;
 785
 786   /* Blocks that are targets of exception edges may have some
 787      artificial uses.  These are logically at the top of the block.
 788
 789      Most blocks have artificial uses at the bottom of the block.  */
 790   df_ref *artificial_uses;
 791 };
 792
 793
 794 /* Reaching definitions.  All bitmaps are indexed by the id field of
 795    the ref except sparse_kill which is indexed by regno.  */
 796 struct df_rd_bb_info
 797 {
 798   /* Local sets to describe the basic blocks.   */
 799   bitmap kill;
 800   bitmap sparse_kill;
 801   bitmap gen;   /* The set of defs generated in this block.  */
 802
 803   /* The results of the dataflow problem.  */
 804   bitmap in;    /* At the top of the block.  */
 805   bitmap out;   /* At the bottom of the block.  */
 806 };
 807
 808
 809 /* Multiple reaching definitions.  All bitmaps are referenced by the
 810    register number.  */
 811
 812 struct df_md_bb_info
 813 {
 814   /* Local sets to describe the basic blocks.  */
 815   bitmap gen;    /* Partial/conditional definitions live at BB out.  */
 816   bitmap kill;   /* Other definitions that are live at BB out.  */
 817   bitmap init;   /* Definitions coming from dominance frontier edges. */
 818
 819   /* The results of the dataflow problem.  */
 820   bitmap in;    /* Just before the block itself. */
 821   bitmap out;   /* At the bottom of the block.  */
 822 };
 823
 824
 825 /* Live registers, a backwards dataflow problem.  All bitmaps are
 826    referenced by the register number.  */
 827
 828 struct df_lr_bb_info
 829 {
 830   /* Local sets to describe the basic blocks.  */
 831   bitmap def;   /* The set of registers set in this block
 832                    - except artificial defs at the top.  */
 833   bitmap use;   /* The set of registers used in this block.  */
 834
 835   /* The results of the dataflow problem.  */
 836   bitmap in;    /* Just before the block itself. */
 837   bitmap out;   /* At the bottom of the block.  */
 838 };
 839
 840
 841 /* Uninitialized registers.  All bitmaps are referenced by the
 842    register number.  Anded results of the forwards and backward live
 843    info.  Note that the forwards live information is not available
 844    separately.  */
 845 struct df_live_bb_info
 846 {
 847   /* Local sets to describe the basic blocks.  */
 848   bitmap kill;  /* The set of registers unset in this block.  Calls,
 849                    for instance, unset registers.  */
 850   bitmap gen;   /* The set of registers set in this block.  */
 851
 852   /* The results of the dataflow problem.  */
 853   bitmap in;    /* At the top of the block.  */
 854   bitmap out;   /* At the bottom of the block.  */
 855 };
 856
 857
 858 /* Live registers, a backwards dataflow problem.  These bitmaps are
 859 indexed by the df_byte_lr_offset array which is indexed by pseudo.  */
 860
 861 struct df_byte_lr_bb_info
 862 {
 863   /* Local sets to describe the basic blocks.  */
 864   bitmap def;   /* The set of registers set in this block
 865                    - except artificial defs at the top.  */
 866   bitmap use;   /* The set of registers used in this block.  */
 867
 868   /* The results of the dataflow problem.  */
 869   bitmap in;    /* Just before the block itself. */
 870   bitmap out;   /* At the bottom of the block.  */
 871 };
 872
 873
 874 /* This is used for debugging and for the dumpers to find the latest
 875    instance so that the df info can be added to the dumps.  This
 876    should not be used by regular code.  */
 877 extern struct df *df;
 878 #define df_scan    (df->problems_by_index[DF_SCAN])
 879 #define df_rd      (df->problems_by_index[DF_RD])
 880 #define df_lr      (df->problems_by_index[DF_LR])
 881 #define df_live    (df->problems_by_index[DF_LIVE])
 882 #define df_chain   (df->problems_by_index[DF_CHAIN])
 883 #define df_byte_lr (df->problems_by_index[DF_BYTE_LR])
 884 #define df_note    (df->problems_by_index[DF_NOTE])
 885 #define df_md      (df->problems_by_index[DF_MD])
 886
 887 /* This symbol turns on checking that each modification of the cfg has
 888   been identified to the appropriate df routines.  It is not part of
 889   verification per se because the check that the final solution has
 890   not changed covers this.  However, if the solution is not being
 891   properly recomputed because the cfg is being modified, adding in
 892   calls to df_check_cfg_clean can be used to find the source of that
 893   kind of problem.  */
 894 #if 0
 895 #define DF_DEBUG_CFG
 896 #endif
 897
 898
 899 /* Functions defined in df-core.c.  */
 900
 901 extern void df_add_problem (struct df_problem *);
 902 extern int df_set_flags (int);
 903 extern int df_clear_flags (int);
 904 extern void df_set_blocks (bitmap);
 905 extern void df_remove_problem (struct dataflow *);
 906 extern void df_finish_pass (bool);
 907 extern void df_analyze_problem (struct dataflow *, bitmap, int *, int);
 908 extern void df_analyze (void);
 909 extern int df_get_n_blocks (enum df_flow_dir);
 910 extern int *df_get_postorder (enum df_flow_dir);
 911 extern void df_simple_dataflow (enum df_flow_dir, df_init_function,
 912                                 df_confluence_function_0, df_confluence_function_n,
 913                                 df_transfer_function, bitmap, int *, int);
 914 extern void df_mark_solutions_dirty (void);
 915 extern bool df_get_bb_dirty (basic_block);
 916 extern void df_set_bb_dirty (basic_block);
 917 extern void df_set_bb_dirty_nonlr (basic_block);
 918 extern void df_compact_blocks (void);
 919 extern void df_bb_replace (int, basic_block);
 920 extern void df_bb_delete (int);
 921 extern void df_verify (void);
 922 #ifdef DF_DEBUG_CFG
 923 extern void df_check_cfg_clean (void);
 924 #endif
 925 extern df_ref df_bb_regno_first_def_find (basic_block, unsigned int);
 926 extern df_ref df_bb_regno_last_def_find (basic_block, unsigned int);
 927 extern df_ref df_find_def (rtx, rtx);
 928 extern bool df_reg_defined (rtx, rtx);
 929 extern df_ref df_find_use (rtx, rtx);
 930 extern bool df_reg_used (rtx, rtx);
 931 extern void df_worklist_dataflow (struct dataflow *,bitmap, int *, int);
 932 extern void df_print_regset (FILE *file, bitmap r);
 933 extern void df_print_byte_regset (FILE *file, bitmap r);
 934 extern void df_dump (FILE *);
 935 extern void df_dump_region (FILE *);
 936 extern void df_dump_start (FILE *);
 937 extern void df_dump_top (basic_block, FILE *);
 938 extern void df_dump_bottom (basic_block, FILE *);
 939 extern void df_refs_chain_dump (df_ref *, bool, FILE *);
 940 extern void df_regs_chain_dump (df_ref,  FILE *);
 941 extern void df_insn_debug (rtx, bool, FILE *);
 942 extern void df_insn_debug_regno (rtx, FILE *);
 943 extern void df_regno_debug (unsigned int, FILE *);
 944 extern void df_ref_debug (df_ref, FILE *);
 945 extern void debug_df_insn (rtx);
 946 extern void debug_df_regno (unsigned int);
 947 extern void debug_df_reg (rtx);
 948 extern void debug_df_defno (unsigned int);
 949 extern void debug_df_useno (unsigned int);
 950 extern void debug_df_ref (df_ref);
 951 extern void debug_df_chain (struct df_link *);
 952
 953 /* Functions defined in df-problems.c. */
 954
 955 extern struct df_link *df_chain_create (df_ref, df_ref);
 956 extern void df_chain_unlink (df_ref);
 957 extern void df_chain_copy (df_ref, struct df_link *);
 958 extern bitmap df_get_live_in (basic_block);
 959 extern bitmap df_get_live_out (basic_block);
 960 extern void df_grow_bb_info (struct dataflow *);
 961 extern void df_chain_dump (struct df_link *, FILE *);
 962 extern void df_print_bb_index (basic_block bb, FILE *file);
 963 extern void df_rd_add_problem (void);
 964 extern void df_rd_simulate_artificial_defs_at_top (basic_block, bitmap);
 965 extern void df_rd_simulate_one_insn (basic_block, rtx, bitmap);
 966 extern void df_lr_add_problem (void);
 967 extern void df_lr_verify_transfer_functions (void);
 968 extern void df_live_verify_transfer_functions (void);
 969 extern void df_live_add_problem (void);
 970 extern void df_live_set_all_dirty (void);
 971 extern void df_chain_add_problem (unsigned int);
 972 extern void df_byte_lr_add_problem (void);
 973 extern int df_byte_lr_get_regno_start (unsigned int);
 974 extern int df_byte_lr_get_regno_len (unsigned int);
 975 extern void df_byte_lr_simulate_defs (rtx, bitmap);
 976 extern void df_byte_lr_simulate_uses (rtx, bitmap);
 977 extern void df_byte_lr_simulate_artificial_refs_at_top (basic_block, bitmap);
 978 extern void df_byte_lr_simulate_artificial_refs_at_end (basic_block, bitmap);
 979 extern void df_note_add_problem (void);
 980 extern void df_md_add_problem (void);
 981 extern void df_md_simulate_artificial_defs_at_top (basic_block, bitmap);
 982 extern void df_md_simulate_one_insn (basic_block, rtx, bitmap);
 983 extern void df_simulate_find_noclobber_defs (rtx, bitmap);
 984 extern void df_simulate_find_defs (rtx, bitmap);
 985 extern void df_simulate_defs (rtx, bitmap);
 986 extern void df_simulate_uses (rtx, bitmap);
 987 extern void df_simulate_initialize_backwards (basic_block, bitmap);
 988 extern void df_simulate_one_insn_backwards (basic_block, rtx, bitmap);
 989 extern void df_simulate_finalize_backwards (basic_block, bitmap);
 990 extern void df_simulate_initialize_forwards (basic_block, bitmap);
 991 extern void df_simulate_one_insn_forwards (basic_block, rtx, bitmap);
 992
 993 /* Functions defined in df-scan.c.  */
 994
 995 extern void df_scan_alloc (bitmap);
 996 extern void df_scan_add_problem (void);
 997 extern void df_grow_reg_info (void);
 998 extern void df_grow_insn_info (void);
 999 extern void df_scan_blocks (void);
1000 extern df_ref df_ref_create (rtx, rtx *, rtx,basic_block,
1001                                      enum df_ref_type, int ref_flags,
1002                                      int, int, enum machine_mode);
1003 extern void df_ref_remove (df_ref);
1004 extern struct df_insn_info * df_insn_create_insn_record (rtx);
1005 extern void df_insn_delete (basic_block, unsigned int);
1006 extern void df_bb_refs_record (int, bool);
1007 extern bool df_insn_rescan (rtx);
1008 extern bool df_insn_rescan_debug_internal (rtx);
1009 extern void df_insn_rescan_all (void);
1010 extern void df_process_deferred_rescans (void);
1011 extern void df_recompute_luids (basic_block);
1012 extern void df_insn_change_bb (rtx, basic_block);
1013 extern void df_maybe_reorganize_use_refs (enum df_ref_order);
1014 extern void df_maybe_reorganize_def_refs (enum df_ref_order);
1015 extern void df_ref_change_reg_with_loc (int, int, rtx);
1016 extern void df_notes_rescan (rtx);
1017 extern void df_hard_reg_init (void);
1018 extern void df_update_entry_block_defs (void);
1019 extern void df_update_exit_block_uses (void);
1020 extern void df_update_entry_exit_and_calls (void);
1021 extern bool df_hard_reg_used_p (unsigned int);
1022 extern unsigned int df_hard_reg_used_count (unsigned int);
1023 extern bool df_regs_ever_live_p (unsigned int);
1024 extern void df_set_regs_ever_live (unsigned int, bool);
1025 extern void df_compute_regs_ever_live (bool);
1026 extern bool df_read_modify_subreg_p (rtx);
1027 extern void df_scan_verify (void);
1028
1029 /* Functions defined in df-byte-scan.c.  */
1030 extern bool df_compute_accessed_bytes (df_ref, enum df_mm,
1031                                        unsigned int *, unsigned int *);
1032
1033
1034 /* Get basic block info.  */
1035
1036 static inline struct df_scan_bb_info *
1037 df_scan_get_bb_info (unsigned int index)
1038 {
1039   if (index < df_scan->block_info_size)
1040     return (struct df_scan_bb_info *) df_scan->block_info[index];
1041   else
1042     return NULL;
1043 }
1044
1045 static inline struct df_rd_bb_info *
1046 df_rd_get_bb_info (unsigned int index)
1047 {
1048   if (index < df_rd->block_info_size)
1049     return (struct df_rd_bb_info *) df_rd->block_info[index];
1050   else
1051     return NULL;
1052 }
1053
1054 static inline struct df_lr_bb_info *
1055 df_lr_get_bb_info (unsigned int index)
1056 {
1057   if (index < df_lr->block_info_size)
1058     return (struct df_lr_bb_info *) df_lr->block_info[index];
1059   else
1060     return NULL;
1061 }
1062
1063 static inline struct df_md_bb_info *
1064 df_md_get_bb_info (unsigned int index)
1065 {
1066   if (index < df_md->block_info_size)
1067     return (struct df_md_bb_info *) df_md->block_info[index];
1068   else
1069     return NULL;
1070 }
1071
1072 static inline struct df_live_bb_info *
1073 df_live_get_bb_info (unsigned int index)
1074 {
1075   if (index < df_live->block_info_size)
1076     return (struct df_live_bb_info *) df_live->block_info[index];
1077   else
1078     return NULL;
1079 }
1080
1081 static inline struct df_byte_lr_bb_info *
1082 df_byte_lr_get_bb_info (unsigned int index)
1083 {
1084   if (index < df_byte_lr->block_info_size)
1085     return (struct df_byte_lr_bb_info *) df_byte_lr->block_info[index];
1086   else
1087     return NULL;
1088 }
1089
1090 /* Get the artificial defs for a basic block.  */
1091
1092 static inline df_ref *
1093 df_get_artificial_defs (unsigned int bb_index)
1094 {
1095   return df_scan_get_bb_info (bb_index)->artificial_defs;
1096 }
1097
1098
1099 /* Get the artificial uses for a basic block.  */
1100
1101 static inline df_ref *
1102 df_get_artificial_uses (unsigned int bb_index)
1103 {
1104   return df_scan_get_bb_info (bb_index)->artificial_uses;
1105 }
1106
1107
1108 /* web */
1109
1110 /* This entry is allocated for each reference in the insn stream.  */
1111 struct web_entry
1112 {
1113   /* Pointer to the parent in the union/find tree.  */
1114   struct web_entry *pred;
1115   /* Newly assigned register to the entry.  Set only for roots.  */
1116   rtx reg;
1117   void* extra_info;
1118 };
1119
1120 extern struct web_entry *unionfind_root (struct web_entry *);
1121 extern bool unionfind_union (struct web_entry *, struct web_entry *);
1122 extern void union_defs (df_ref, struct web_entry *,
1123                         unsigned int *used, struct web_entry *,
1124                         bool (*fun) (struct web_entry *, struct web_entry *));
1125
1126 #endif /* GCC_DF_H */